SkIRect Reference

IRect

Struct SkIRect

SkIRect holds four 32-bit integer coordinates describing the upper and lower bounds of a rectangle. SkIRect may be created from outer bounds or from position, width, and height. SkIRect describes an area; if its right is less than or equal to its left, or if its bottom is less than or equal to its top, it is considered empty.

Overview

Related Function

SkIRect global, struct, and class related member functions share a topic.

Member Function

SkIRect member functions read and modify the structure properties.

Member

Members

SkIRect members may be read and written directly without using a member function.

Members

Constructor

SkIRect can be constructed or initialized by these functions, including C++ class constructors.

MakeEmpty

Returns constructed IRect set to (0, 0, 0, 0). Many other rectangles are empty; if left is equal to or greater than right, or if top is equal to or greater than bottom. Setting all members to zero is a convenience, but does not designate a special empty rectangle.

Return Value

bounds (0, 0, 0, 0)

Example

Example Output

MakeEmpty isEmpty: true
offset rect isEmpty: true
inset rect isEmpty: true
outset rect isEmpty: false

See Also

EmptyIRect isEmpty setEmpty SkRect::MakeEmpty


MakeWH

Returns constructed IRect set to (0, 0, w, h). Does not validate input; w or h may be negative.

Parameters

Return Value

bounds (0, 0, w, h)

Example

Example Output

all equal

See Also

MakeSize MakeXYWH SkRect::MakeWH SkRect::MakeIWH


MakeSize

Returns constructed IRect set to (0, 0, size.width, size.height). Does not validate input; size.width or size.height may be negative.

Parameters

Return Value

bounds (0, 0, size.width, size.height)

Example

Example Output

round width: 26  height: 36
floor width: 25  height: 35

See Also

MakeWH MakeXYWH SkRect::Make[2] SkRect::MakeIWH


MakeLTRB

Returns constructed IRect set to (l, t, r, b). Does not sort input; IRect may result in fLeft greater than fRight, or fTop greater than fBottom.

Parameters

Return Value

bounds (l, t, r, b)

Example

Example Output

rect: 5, 35, 15, 25  isEmpty: true
rect: 5, 25, 15, 35  isEmpty: false

See Also

MakeXYWH SkRect::MakeLTRB


MakeXYWH

Returns constructed IRect set to: (x, y, x + w, y + h). Does not validate input; w or h may be negative.

Parameters

Return Value

bounds at (x, y) with width w and height h

Example

Example Output

rect: 5, 35, -10, 60  isEmpty: true
rect: -10, 35, 5, 60  isEmpty: false

See Also

MakeLTRB SkRect::MakeXYWH


Property

left

Returns left edge of IRect, if sorted. Call sort to reverse fLeft and fRight if needed.

Return Value

fLeft

Example

Example Output

unsorted.fLeft: 15 unsorted.left(): 15
sorted.fLeft: 10 sorted.left(): 10

See Also

fLeft x SkRect::left()


top

Returns top edge of IRect, if sorted. Call isEmpty to see if IRect may be invalid, and sort to reverse fTop and fBottom if needed.

Return Value

fTop

Example

Example Output

unsorted.fTop: 25 unsorted.top(): 25
sorted.fTop: 5 sorted.top(): 5

See Also

fTop y SkRect::top()


right

Returns right edge of IRect, if sorted. Call sort to reverse fLeft and fRight if needed.

Return Value

fRight

Example

Example Output

unsorted.fRight: 10 unsorted.right(): 10
sorted.fRight: 15 sorted.right(): 15

See Also

fRight SkRect::right()


bottom

Returns bottom edge of IRect, if sorted. Call isEmpty to see if IRect may be invalid, and sort to reverse fTop and fBottom if needed.

Return Value

fBottom

Example

Example Output

unsorted.fBottom: 5 unsorted.bottom(): 5
sorted.fBottom: 25 sorted.bottom(): 25

See Also

fBottom SkRect::bottom()


x

Returns left edge of IRect, if sorted. Call isEmpty to see if IRect may be invalid, and sort to reverse fLeft and fRight if needed.

Return Value

fLeft

Example

Example Output

unsorted.fLeft: 15 unsorted.x(): 15
sorted.fLeft: 10 sorted.x(): 10

See Also

fLeft left y SkRect::x()


y

Returns top edge of IRect, if sorted. Call isEmpty to see if IRect may be invalid, and sort to reverse fTop and fBottom if needed.

Return Value

fTop

Example

Example Output

unsorted.fTop: 25 unsorted.y(): 25
sorted.fTop: 5 sorted.y(): 5

See Also

fTop top x SkRect::y()


width

Returns span on the x-axis. This does not check if IRect is sorted, or if result fits in 32-bit signed integer; result may be negative.

Return Value

fRight minus fLeft

Example

Example Output

unsorted width: -5
large width: -5

See Also

height width64 height64 SkRect::width()


width64

Returns span on the x-axis. This does not check if IRect is sorted, so the result may be negative. This is safer than calling width since width might overflow in its calculation.

Return Value

fRight minus fLeft cast to int64_t

Example

Example Output

width: -5 width64: 4294967291

See Also

width height height64 SkRect::width()


height

Returns span on the y-axis. This does not check if IRect is sorted, or if result fits in 32-bit signed integer; result may be negative.

Return Value

fBottom minus fTop

Example

Example Output

unsorted height: -5
large height: -5

See Also

width SkRect::height()


height64

Returns span on the y-axis. This does not check if IRect is sorted, so the result may be negative. This is safer than calling height since height might overflow in its calculation.

Return Value

fBottom minus fTop cast to int64_t

Example

Example Output

height: -5 height64: 4294967291

See Also

width height width64 SkRect::height()


size

Returns spans on the x-axis and y-axis. This does not check if IRect is sorted, or if result fits in 32-bit signed integer; result may be negative.

Return Value

ISize (width, height)

Example

Example Output

original rect: 20, 30, 40, 50  size: 20, 20
offset rect: 40, 50, 60, 70  size: 20, 20
outset rect: 20, 30, 80, 90  size: 60, 60

See Also

height width MakeSize


isEmpty

Returns true if width or height .

Return Value

true if width or height are zero or negative

Example

Example Output

rect: {20, 40, 10, 50} is empty
sorted: {10, 40, 20, 50} is not empty
rect: {20, 40, 20, 50} is empty
sorted: {20, 40, 20, 50} is empty

See Also

EmptyIRect MakeEmpty sort SkRect::isEmpty


isEmpty64

Returns true if fLeft is equal to or greater than fRight, or if fTop is equal to or greater than fBottom. Call sort to reverse rectangles with negative width64 or height64.

Return Value

true if width64 or height64 are zero or negative

Example

Example Output

rect: {20, 40, 10, 50} is empty
sorted: {10, 40, 20, 50} is not empty
rect: {20, 40, 20, 50} is empty
sorted: {20, 40, 20, 50} is empty

See Also

EmptyIRect MakeEmpty sort SkRect::isEmpty


Operator

SkIRect operators inline class member functions with arithmetic equivalents.

operator==

Returns true if all members in a: fLeft, fTop, fRight, and fBottom; are identical to corresponding members in b.

Parameters

Return Value

true if members are equal

Example

Example Output

test == sorted

See Also

operator!=(const SkIRect& a, const SkIRect& b)


operator!=

Returns true if any member in a: fLeft, fTop, fRight, and fBottom; is not identical to the corresponding member in b.

Parameters

Return Value

true if members are not equal

Example

Example Output

test != sorted

See Also

operator==(const SkIRect& a, const SkIRect& b)


Set

setEmpty

Sets IRect to (0, 0, 0, 0).

Many other rectangles are empty; if left is equal to or greater than right, or if top is equal to or greater than bottom. Setting all members to zero is a convenience, but does not designate a special empty rectangle.

Example

Example Output

rect: {3, 4, 1, 2} is empty
rect: {0, 0, 0, 0} is empty

See Also

MakeEmpty SkRect::setEmpty


set

Sets IRect to (left, top, right, bottom). left and right are not sorted; left is not necessarily less than right. top and bottom are not sorted; top is not necessarily less than bottom.

Parameters

Example

Example Output

rect1: {3, 4, 1, 2}
rect2: {3, 4, 1, 2}

See Also

setLTRB setXYWH SkRect::set[2][3][4]


setLTRB

Sets IRect to (left, top, right, bottom). left and right are not sorted; left is not necessarily less than right. top and bottom are not sorted; top is not necessarily less than bottom.

Parameters

Example

Example Output

rect1: {3, 4, 1, 2}
rect2: {3, 4, 1, 2}

See Also

set setXYWH SkRect::setLTRB


setXYWH

Sets IRect to: (x, y, x + width, y + height). Does not validate input; width or height may be negative.

Parameters

Example

Example Output

rect: 5, 35, -10, 60  isEmpty: true
rect: -10, 35, 5, 60  isEmpty: false

See Also

MakeXYWH setLTRB set SkRect::setXYWH


Inset Outset Offset

makeOffset

Returns IRect offset by (dx, dy).

If dx is negative, IRect returned is moved to the left. If dx is positive, IRect returned is moved to the right. If dy is negative, IRect returned is moved upward. If dy is positive, IRect returned is moved downward.

Parameters

Return Value

IRect offset by dx and dy, with original width and height

Example

Example Output

rect: 10, 50, 20, 60  isEmpty: false
rect: 25, 82, 35, 92  isEmpty: false

See Also

offset[2] makeInset makeOutset SkRect::makeOffset


makeInset

Returns IRect, inset by (dx, dy).

If dx is negative, IRect returned is wider. If dx is positive, IRect returned is narrower. If dy is negative, IRect returned is taller. If dy is positive, IRect returned is shorter.

Parameters

Return Value

IRect inset symmetrically left and right, top and bottom

Example

Example Output

rect: 10, 50, 20, 60  isEmpty: false
rect: 25, 82, 5, 28  isEmpty: true

See Also

inset makeOffset makeOutset SkRect::makeInset


makeOutset

Returns IRect, outset by (dx, dy).

If dx is negative, IRect returned is narrower. If dx is positive, IRect returned is wider. If dy is negative, IRect returned is shorter. If dy is positive, IRect returned is taller.

Parameters

Return Value

IRect outset symmetrically left and right, top and bottom

Example

Example Output

rect: 10, 50, 20, 60  isEmpty: false
rect: -5, 18, 35, 92  isEmpty: false

See Also

outset makeOffset makeInset SkRect::makeOutset


offset

Offsets IRect by adding dx to fLeft, fRight; and by adding dy to fTop, fBottom.

If dx is negative, moves IRect returned to the left. If dx is positive, moves IRect returned to the right. If dy is negative, moves IRect returned upward. If dy is positive, moves IRect returned downward.

Parameters

Example

Example Output

rect: 15, 27, 55, 86

See Also

offsetTo makeOffset SkRect::offset[2]


Offsets IRect by adding delta.fX to fLeft, fRight; and by adding delta.fY to fTop, fBottom.

If delta.fX is negative, moves IRect returned to the left. If delta.fX is positive, moves IRect returned to the right. If delta.fY is negative, moves IRect returned upward. If delta.fY is positive, moves IRect returned downward.

Parameters

Example

Example Output

rect: 15, 27, 55, 86

See Also

offsetTo makeOffset SkRect::offset[2]


offsetTo

Offsets IRect so that fLeft equals newX, and fTop equals newY. width and height are unchanged.

Parameters

Example

Example Output

rect: 15, 27, 55, 86

See Also

offset[2] makeOffset setXYWH SkRect::offsetTo


inset

Insets IRect by (dx,dy).

If dx is positive, makes IRect narrower. If dx is negative, makes IRect wider. If dy is positive, makes IRect shorter. If dy is negative, makes IRect taller.

Parameters

Example

Example Output

rect: 15, 27, 45, 60

See Also

outset makeInset SkRect::inset


outset

Outsets IRect by (dx, dy).

If dx is positive, makes IRect wider. If dx is negative, makes IRect narrower. If dy is positive, makes IRect taller. If dy is negative, makes IRect shorter.

Parameters

Example

Example Output

rect: 5, 1, 55, 86

See Also

inset makeOutset SkRect::outset


Intersection

IRects intersect when they enclose a common area. To intersect, each of the pair must describe area; fLeft is less than fRight, and fTop is less than fBottom; empty() returns false. The intersection of IRect pair can be described by: (max(a.fLeft, b.fLeft), max(a.fTop, b.fTop),             min(a.fRight, b.fRight), min(a.fBottom, b.fBottom)).

The intersection is only meaningful if the resulting IRect is not empty and describes an area: fLeft is less than fRight, and fTop is less than fBottom.

adjust

Adjusts IRect by adding dL to fLeft, dT to fTop, dR to fRight, and dB to fBottom.

If dL is positive, narrows IRect on the left. If negative, widens it on the left. If dT is positive, shrinks IRect on the top. If negative, lengthens it on the top. If dR is positive, narrows IRect on the right. If negative, widens it on the right. If dB is positive, shrinks IRect on the bottom. If negative, lengthens it on the bottom.

The resulting IRect is not checked for validity. Thus, if the resulting IRect left is greater than right, the IRect will be considered empty. Call sort after this call if that is not the desired behavior.

Parameters

Example

Example Output

rect: 10, 10, 20, 20

See Also

inset outset


contains

Returns true if: fLeft <= x < fRight && fTop <= y < fBottom. Returns false if IRect is empty.

Considers input to describe constructed IRect: (x, y, x + 1, y + 1) and returns true if constructed area is completely enclosed by IRect area.

Parameters

Return Value

true if (x, y) is inside IRect

Example

Example Output

rect: (30, 50, 40, 60) contains (30, 50)
rect: (30, 50, 40, 60) does not contain (40, 50)
rect: (30, 50, 40, 60) does not contain (30, 60)

See Also

containsNoEmptyCheck[2] SkRect::contains[2][3]


Constructs IRect to intersect from (left, top, right, bottom). Does not sort construction.

Returns true if IRect contains construction. Returns false if IRect is empty or construction is empty.

Parameters

Return Value

true if all sides of IRect are outside construction

Example

Example Output

rect: (30, 50, 40, 60) contains (30, 50, 31, 51)
rect: (30, 50, 40, 60) does not contain (39, 49, 40, 50)
rect: (30, 50, 40, 60) does not contain (29, 59, 30, 60)

See Also

containsNoEmptyCheck[2] SkRect::contains[2][3]


Returns true if IRect contains r. Returns false if IRect is empty or r is empty.

IRect contains r when IRect area completely includes r area.

Parameters

Return Value

true if all sides of IRect are outside r

Example

Example Output

rect: (30, 50, 40, 60) contains (30, 50, 31, 51)
rect: (30, 50, 40, 60) does not contain (39, 49, 40, 50)
rect: (30, 50, 40, 60) does not contain (29, 59, 30, 60)

See Also

containsNoEmptyCheck[2] SkRect::contains[2][3]


Returns true if IRect contains r. Returns false if IRect is empty or r is empty.

IRect contains r when IRect area completely includes r area.

Parameters

Return Value

true if all sides of IRect are outside r

Example

Example Output

rect: (30, 50, 40, 60) contains (30, 50, 31, 51)
rect: (30, 50, 40, 60) does not contain (39, 49, 40, 50)
rect: (30, 50, 40, 60) does not contain (29, 59, 30, 60)

See Also

containsNoEmptyCheck[2] SkRect::contains[2][3]


containsNoEmptyCheck

Constructs IRect from (left, top, right, bottom). Does not sort construction.

Returns true if IRect contains construction. Asserts if IRect is empty or construction is empty, and if SK_DEBUG is defined.

Return is undefined if IRect is empty or construction is empty.

Parameters

Return Value

true if all sides of IRect are outside construction

Example

Example Output

rect: (30, 50, 40, 60) contains (30, 50, 31, 51)
rect: (30, 50, 40, 60) does not contain (39, 49, 40, 50)
rect: (30, 50, 40, 60) does not contain (29, 59, 30, 60)

See Also

contains[2][3][4] SkRect::contains[2][3]


Returns true if IRect contains construction. Asserts if IRect is empty or construction is empty, and if SK_DEBUG is defined.

Return is undefined if IRect is empty or construction is empty.

Parameters

Return Value

true if all sides of IRect are outside r

Example

Example Output

rect: (30, 50, 40, 60) contains (30, 50, 31, 51)
rect: (30, 50, 40, 60) does not contain (39, 49, 40, 50)
rect: (30, 50, 40, 60) does not contain (29, 59, 30, 60)

See Also

contains[2][3][4] SkRect::contains[2][3]


intersect

Returns true if IRect intersects r, and sets IRect to intersection. Returns false if IRect does not intersect r, and leaves IRect unchanged.

Returns false if either r or IRect is empty, leaving IRect unchanged.

Parameters

Return Value

true if r and IRect have area in common

Example

Example Output

intersection: 30, 60, 50, 80

See Also

Intersects intersectNoEmptyCheck join[2] SkRect::intersect[2][3]


Returns true if a intersects b, and sets IRect to intersection. Returns false if a does not intersect b, and leaves IRect unchanged.

Returns false if either a or b is empty, leaving IRect unchanged.

Parameters

Return Value

true if a and b have area in common

Example

Example Output

intersection: 30, 60, 50, 80

See Also

Intersects intersectNoEmptyCheck join[2] SkRect::intersect[2][3]


intersectNoEmptyCheck

Returns true if a intersects b, and sets IRect to intersection. Returns false if a does not intersect b, and leaves IRect unchanged.

Asserts if either a or b is empty, and if SK_DEBUG is defined.

Parameters

Return Value

true if a and b have area in common

Example

Example Output

intersection: 30, 60, 50, 80

See Also

Intersects intersect[2][3] join[2] SkRect::intersect[2][3]


Constructs IRect to intersect from (left, top, right, bottom). Does not sort construction.

Returns true if IRect intersects construction, and sets IRect to intersection. Returns false if IRect does not intersect construction, and leaves IRect unchanged.

Returns false if either construction or IRect is empty, leaving IRect unchanged.

Parameters

Return Value

true if construction and IRect have area in common

Example

Example Output

intersection: 30, 60, 50, 80

See Also

intersectNoEmptyCheck Intersects join[2] SkRect::intersect[2][3]


Intersects

Returns true if a intersects b. Returns false if either a or b is empty, or do not intersect.

Parameters

Return Value

true if a and b have area in common

Example

Example Output

intersection

See Also

IntersectsNoEmptyCheck intersect[2][3] SkRect::intersect[2][3]


IntersectsNoEmptyCheck

Returns true if a intersects b. Asserts if either a or b is empty, and if SK_DEBUG is defined.

Parameters

Return Value

true if a and b have area in common

Example

Example Output

intersection

See Also

Intersects intersect[2][3] SkRect::intersect[2][3]


Join

join

Constructs IRect to intersect from (left, top, right, bottom). Does not sort construction.

Sets IRect to the union of itself and the construction.

Has no effect if construction is empty. Otherwise, if IRect is empty, sets IRect to construction.

Parameters

Example

Example Output

join: 10, 20, 55, 65

See Also

set SkRect::join[2]


Sets IRect to the union of itself and r.

Has no effect if r is empty. Otherwise, if IRect is empty, sets IRect to r.

Parameters

Example

Example Output

join: 10, 20, 55, 65

See Also

set SkRect::join[2]


Sorting

sort

Swaps fLeft and fRight if fLeft is greater than fRight; and swaps fTop and fBottom if fTop is greater than fBottom. Result may be empty, and width and height will be zero or positive.

Example

Example Output

rect: 30, 50, 20, 10
sorted: 20, 10, 30, 50

See Also

makeSorted SkRect::sort


makeSorted

Returns IRect with fLeft and fRight swapped if fLeft is greater than fRight; and with fTop and fBottom swapped if fTop is greater than fBottom. Result may be empty; and width and height will be zero or positive.

Return Value

sorted IRect

Example

Example Output

rect: 30, 50, 20, 10
sorted: 20, 10, 30, 50

See Also

sort SkRect::makeSorted


EmptyIRect

Returns a reference to immutable empty IRect, set to (0, 0, 0, 0).

Return Value

global IRect set to all zeroes

Example

Example Output

rect: 0, 0, 0, 0

See Also

MakeEmpty


MakeLargest

Deprecated.